19479917 has 2 divisors, whose sum is σ = 19479918. Its totient is φ = 19479916.

The previous prime is 19479869. The next prime is 19479931. The reversal of 19479917 is 71997491.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19412836 + 67081 = 4406^2 + 259^2 .

It is a cyclic number.

It is not a de Polignac number, because 19479917 - 2²⁰ = 18431341 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19479937) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9739958 + 9739959.

It is an arithmetic number, because the mean of its divisors is an integer number (9739959).

Almost surely, 2^19479917 is an apocalyptic number.

It is an amenable number.

19479917 is a deficient number, since it is larger than the sum of its proper divisors (1).

19479917 is an equidigital number, since it uses as much as digits as its factorization.

19479917 is an evil number, because the sum of its binary digits is even.

The product of its digits is 142884, while the sum is 47.

The square root of 19479917 is about 4413.6058954102. The cubic root of 19479917 is about 269.0681962500.

The spelling of 19479917 in words is "nineteen million, four hundred seventy-nine thousand, nine hundred seventeen".